Abstract: A side scan sonar system comprises a sonar transmitter transducer means for transmitting sonar signal pulses so as to produce an arc of insonification extending to one side of a line along the direction of forward motion of a ship. A line array of receiver transducers for receiving echo signals within the arc is also provided. An electronic scanning beamformer is adapted to combine the signals of the transducers of the line array so as to form a directional receiving beam and to steer the beam electronically through a scanning angle within the arc of insonification. A sampling means is arranged to receive the combined signals of the transducers. A sampling control means is synchronized with the transmitted pulses and is operative to control the sampling means to select signals appertaining to a predetermining sector or strip within the scanning angle. The signals provide information signals for a visual display means.